They are much shorter than refracting telescopes, hence, much cheaper to buy and easier to transport.
Isaac Newten
One end of a reflecting telescope is the big hole pointed at the star. The other end of the reflecting telescope has a lens called an eyepiece.
"To build a large refracting telescope would require very strong supports to hold large enough lenses. These supports would tend to block out important light. So the refracting telescope is limited in its use. Today most large telescopes are reflecting telescopes." ~ BYU Home Study Astronomy course
A refracting telescope is a type of telescope that has a large thin lense at the front and a smaller thicker lense at the end where the eyepiece is. Refracting telescopes use lenses unlike reflecting telescopes that use mirrors to reflect the light. This is a good image of a refracting and reflecting telescope: [See related link]
Reflector.
A reflector telescope collects light with a mirror. The mirror is located at the back of the telescope and reflects the incoming light to a focal point where it is then collected by an eyepiece for viewing.
In front of the mirror
In front of the mirror
Isaac Newton invented the reflecting telescope.
It is a reflecting telescope
A reflecting telescope has both magnifying mirrors and lenses to focus the image on the eyepiece. A refracting telescope uses only lenses to magnify and focus. A reflecting telescope can be much smaller, because the light can travel through the barrel of the telescope several times, being magnified with each reflection. This is why most large modern telescopes are reflectors.
A reflecting telescope uses mirrors while refracting telescopes uses lens. The refracting telescope also had chromatic aberration and bad resolution while the reflecting telescope had none of these.